Bed side pulmonary function tests 7

pulmonary function tests

1. Bed side Pulmonary F unction Tests 1 [email protected]

2. Pulmonary function tests have been used traditionally in the preoperative assessment before any major surgery. INDICATIONS To predict the presence of pulmonary dysfunction To know the functional nature of disease (obstructive or restrictive. ) To assess the severity of disease To assess the progression of disease To assess the response to treatment To identify patients at increased risk of morbidity and mortality, undergoing pulmonary resection. 2 [email protected]

3. To identify patients at perioperative risk of pulmonary complications Degree and severity of impairment Identify the site of airway obstruction 3 [email protected]

4. Sabrasez breath holding test: Ask the patient to take a full but not too deep breath & hold it as long as possible. >25 SEC.-NORMAL Cardiopulmonary Reserve 15-25 SEC- LIMITED CardioPulmonary Reserve <15 SEC- VERY POOR CardioPulmonary Reserve ( Contraindication for elective surgery) 25- 30 SEC - 3500 ml VC 20 – 25 SEC - 3000 ml VC 15 - 20 SEC - 2500 ml VC 10 - 15 SEC - 2000 ml VC 5 - 10 SEC - 1500 ml VC 4 [email protected]

5. Breath Holding Test 5 [email protected]

6. 2) Single breath count: After deep breath, hold it and start counting till the next breath. Normal- 30-40 COUNT Indicates vital capacity 6 [email protected]

7. 3) SNIDER’SMATCH BLOWING TEST: Measures Maximum Breathing Capacity. Should take 6 attempts Ask to blow a match stick from a distance of 6” (15 cms ) with Mouth wide open Chin rested/supported No pursed lips No head movement No air movement in the room Mouth and match stick at the same level 7 [email protected]

8. Match Blowing Test 8 [email protected]

9. Can not blow out a match MBC < 60 L/min FEV1 < 1.6L Able to blow out a match MBC > 60 L/min FEV1 > 1.6L MODIFIED MATCH TEST of Olsen: DISTANCE MBC 9” >150 L/MIN. 6” >60 L/MIN. 3” > 40 L/MIN. 9 [email protected]

10. 4 ) GREENE & BEROWITZ COUGH TEST: DEEP BREATH F/BY COUGH ABILITY TO COUGH STRENGTH EFFECTIVENESS INADEQUATE COUGH : FVC<20 mL/Kg FEV1 < 15 ml/Kg PEFR < 200 L/min. VC ~ 3 TIMES TV FOR EFFECTIVE COUGH. A wet productive cough / self propagated paroxysms of coughing – patient susceptible for pulmonary Complication. 10 [email protected]

11. 5) FORCED EXPIRATORY TIME: After deep breath, exhale maximally and forcefully & keep stethoscope over trachea & listen. Normal FET – 3-5 SECS. Obstructive Lung Disease - > 6 SEC Restrictive Lung Disease - < 3 SEC 11 [email protected]

12. Auscultation over Trachea 12 [email protected]

13. 6. RESPIRATORY RATE Essential yet frequently undervalued component of PFT Imp. evaluator in weaning & extubation protocols Increase RR ‐ muscle fatigue ‐work load ‐ weaning fails 13 [email protected]

14. 7 ) DE BONO’S WHISTLE BLOWING TEST : MEASURES PEFR . Patient blows down a wide bore tube at the end of which is a whistle, on the side is a hole with adjustable knob . As subject blows → whistle blows, leak hole is gradually increased till the intensity of whistle disappears . At the last position at which the whistle can be blown , the PEFR can be read off the scale. 14 [email protected]

15. DE BONO’S WHISTLE 15 [email protected]

16. 8 )Wright ‘s Respirometer : measures V T and minute volume Simple and rapid Instrument- compact, light and portable. Disadvantage: It under- reads at low flow rates and over- reads at high flow rates. Can be connected to endo tracheal tube or face mask Prior explanation to patient is needed. 16 [email protected]

17. 17 [email protected]

18. Contd … Ideally done in sitting position. MV- instrument record for 1 min. And read directly V T -calculated and dividing MV by counting Respiratory Rate. Accurate measurement in the range of 3.7-20 L/min.(±10%) USES: 1)Bedside PFT 2) ICU – Weaning Pts. from Ventilator . 18 [email protected]

19. 9) MICROSPIROMETERS – MEASURE VC. 19 [email protected]

20. 10) BED SIDE PULSE OXIMETRY 11) ABG. 20 [email protected]

21. References SNIDER,T. H.Simple Bedside Test of Respiratory Function. J. Am. Med. Assoc. 170:1631, 1959. CARILLI, A. D. and J. R. HENDERSON. Estimation of Ventilatory Function by Blowing Out a Match. Am. Rev. Resp. Dis. 89:680, 1964. OLSEN, C. R. The Match Test: A Measure of Ventilatory Function. Am. Rev. Resp. Dis. 86:37,1962. WRIGHT, B. M. and C. B. McKERROW . Maximum Forced Expiratory Flow Rate as a Measure of Ventilatory Capacity. Br. Med. J. 2:1041, 1959. DE BONO , E. F. A Whistle for Testing Lung Function. Lancet 2:1146, 1963. 21 [email protected]

22. 22 [email protected]